1. Technical Field
Embodiments of the present disclosure generally relate to semiconductor integrated circuits and, more particularly, to internal voltage generation circuits.
2. Related Art
In general, semiconductor devices receive a power supply voltage VDD and a ground voltage VSS from an external system. The received power supply voltage VDD and ground voltage VSS are used to generate internal voltages used in operations of internal circuits of the semiconductor devices. The internal voltages for operating the internal circuits of the semiconductor devices may include a core voltage VCORE. The core voltage VCORE may be supplied to core regions of the semiconductor device. The internal voltages for operating the internal circuits of the semiconductor devices may include a high voltage VPP. The high voltage VPP may be used to drive or overdrive word lines of the semiconductor device. The internal voltages for operating the internal circuits of the semiconductor devices may include a low voltage VBB. The low voltage VBB may be applied to a bulk region (or a substrate) of NMOS transistors in the core region of the semiconductor device.
The core voltage VCORE may be a positive voltage lower than the power supply voltage VDD supplied from the external system. Thus, the core voltage VCORE may be generated by lowering the power supply voltage VDD to a certain level. In contrast, the high voltage VPP may be higher than the power supply voltage VDD. The low voltage VBB may be a negative voltage lower than the ground voltage VSS. Thus, charge pump circuits may be required to generate the high voltage VPP and the low voltage VBB.